progestogen only pill and breast cancer

Last edited 03/2023 and last reviewed 03/2023

A study (n=9498 incident invasive breast cancer [BC]; 18,171 matched controls) found current or recent hormonal contraceptive use linked to similarly increased BC risk, regardless of whether oral combined, POP, or injectable/implant/intrauterine device of progestogen was last used (1):

  • a relative increase of approximately 20% to 30% in breast cancer risk associated with current or recent use of either combined oral or progestagen-only contraceptives
  • when the authors combined the findings with results from previous studies, which included women in a wider age range
    • 15-year absolute excess risk of breast cancer associated with use of oral contraceptives ranged from 8 per 100,000 users (increase in incidence from 0.084% to 0.093%) for use from age 16 to 20 to about 265 per 100,000 users (from 2.0% to 2.2%) for use from age 35 to 39

Reference:

  1. Fitzpatrick D et al. Combined and progestagen-only hormonal contraceptives and breast cancer risk: A UK nested case.control study and meta-analysis. PLOS Medicine March 21st 2023.